Method of making mechanical overlays



Dec. 18, 1951 i FARLEY 2,579,182

METHOD OF MAKING MECHANICAL OVERLAYS Filed Dec. e, 1948 2 SHEETSSHEET 1 INVENTOR.

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METHOD OF MAKING MECHANICAL OVERLAYS Filed Dec. 6, 1948 2 SHEETS-SPEET 2 p "wwm w'm' IN VEN TOR.

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atented fiec. i8, 1951 UNITED STATES PATENT" omcg METHOD OF MAKING MECHANICAL OVERLAYS I I Alfred E. Farley, Chicago, Ill. Application December 6, 1948, Serial No. 63,669

18 Claims. 1

This invention relates to a novel overlay for use in printing apparatus and to a process for making the same.

A major problem that confronts the printing industry relates to the process of making ready the impression surface of printingapparatus. Costly and time consuming hand methods ordinarily are employed in this operation because the mechanical and chemical methods that have thus far been proposed have proven to be unsatisfactory from one standpoint or another. The importance of this problem can be seen when reference is had to the steps that ordinarilyare taken to prepare for printing when using a cylinder press,'i. e., a-printing apparatus wherein an inked flat type formis passed under an impression cylinder that carries the paper or other material to be printed. One of the first operations is to prepare the impression surface by covering it with a number. of sheets of suitable paper. The form of type that has been set up previously is locked in the bed and an accurate and effectiveoverlay for. printing.

impression-is then pulled on a sheet of paper.

Invariably this first pull shows irregularities in the printing; some parts of the printing being so weak that they are unreadable and others being so heavy that the sheet of paper is nearly cut through. The rectification of these in-. equalities, which are caused by variations in the heights of the type, requires great skill and experience on the part of the operator, for unless the'work is done with ability andunder-v standing, the printed sheets will appear patchy and difiicult to read.

' The process of correcting for the variations in the heights of the type, said variations ranging from about 0.0005 inch to about 0.005 inch, is called making ready. It is not unusual for a large form oftype to take 'two or three days to make ready. Conventional practice involves pulling an impression on a thin sheet of paper, cutting out with a sharp instrument those parts of the paper where the printing is too heavy, and pasting bits of tissue paper on those parts of the sheet where the printing is too light. Alternatively, the heavy parts are not cut out, but layers of tissue are pasted onto the sheet where the impressions are weak. When the sheet is completed, it is placed on the impression surface in a position corresponding exactly with that part of the form which requires the particular treatment. Another impression-is then pulled and the work of cutting out and patching up is continued until the impression presents an even and-regular .appearance5- It is another object of this invention to provide means for compensating for differences in type height in printing by a relatively simple and in,-' expensive process involvinga single impression ofan uninked printing form. a It is a further object'of one embodiment, of the present-invention to prepare an overlay di rectly onthe tympan roll by arapid process, which eliminates the. necessity for removing'the overlay'for processing: thereof, thereby insuring substantially perfect register. v n Still another object of this invention is to prepare an overlay for printing by a single C011: tacting of the type form with means associated with the tympan roll and adapted to receive and. retain impressions.

Briefly. stated, my invention comprises, .(ll' methods of. forming an overlay directly on the platen or impression cylinder of a printing ma-, chine by a single impression of the type form. and (2) new. articles. of manufacture-to,wit, the overlays so formed. Theimpression mem: ber of the printing apparatus is prepared by plac ing thereon means for receiving and retaining an impression. The type form is then brought to bear ontheassembly and an impression of the: type is formed on said means. If necessary, the' means is caused. to harden or congealin order to permanently'retain the impression. The means is now low where the type is high and high where the type is low and is in direct and perfect register with the type. A suitable top sheet or sheets may then be placed over said means and'the apparatus is then ready for print-.; ing. Although special inks and the like maybe used, they are not essential. a

In order that my invention may be more fully disclosed, reference is had to the accompanying drawings; which illustrateseveral forms of vim-e pression -receiving and retaining means-which may be employed in the practice-of my. invention and which embody the foregoing and such other principles, advantages or capabilities as may be pointed out as this description proceeds, or as are inherent in the present invention. For purposes of clarity in exposition, the following description is explicit, and the accompanying draw-' ings are detailed, but it is distinctly to be understood that said exposition is illustrative only, and that .my invention is not restricted tothe particular details recited in the specification or shown in the drawings.

In the drawings:

Figures 1-4 are elevational views taken in cross-section through a form of type and a printing roll, and illustrate successive steps whereby one embodiment of my novel'mechanical overlay is made ready; V

Figures 5-7 are elevational cross-sectional views illustrating successive steps involved in the manufacture of another embodiment of my invention; and

-Figures 8-1!) are .elevational cross-sectional views illustrating the appearance of a third embodiment of my invention, followingsuccessive steps in its manufacture.

Like reference characters designate like parts in the drawings and in the description thereof which follows:

Referring now in detail to the drawings, Figure 1 shows an assembly or composite [5 that I have found to be especially well suited for practicing my invention. The assembly I5 is made up of special sheets or layers and is adapted to be secured to the impression cylinder or roll 29 of a printing machine. The first layer of the assembly l5 consists of a base'sheet 2| which may have a cellophane surface on that side facing the roll and a tacky and/or pressure sensitive adhesive 22 on the other side thereof. By the term adhesive, as .used throughout the specification and appended claims, is meant any sticky material capable of holding powder pressed against it, and includes such diverse substances as heavy viscous inks, on the one hand,,and the commercial masticused. to cement tile, on the other. A screen 23, whichmay be formed from conventional drafting room linen, for example, is placed over the sheet 2| bearing the. adhesive 22. A third sheet 24 is then placed on top of the screen 23. The third-sheet .24, which may be formed frompaper or the like, is coated on one side with a suitable powder or.. grit 25 such as for example finelydivided iron, manganese, or other metallic or snonmetallic substances. The powder 25 is loosely held on the sheet 24 by means of a suitable adhesive such as starch .or

flour paste. For example, the powder..25 may be mixed with ordinary starch paste made with water and the resultant mixture applied to one side of the sheet 24 and allowed. .to dry. 7 The result is a structure wherein, the individual particles of the powder 25 are'only loosely bound to the sheet 24 and to each other. This sheet 24 is placed on the screen 23 with the coated side facing the impression member 20.

The padding 2.6 on the cylinder ordinarily age-9,182 i through the screen 23 and into contact with the powder 25. As a result of this operation, projections l9 consisting of agglomerated powder and adhesive are formed on the base sheet 2| opposite the type faces. The faces of the group 21 of low type as well as of the group 28 of high type act as pressure points, but the faces of the high type cause a greater compression of the powder 25 and "adhesive 22. When the type form is withdrawn from contact with the impression roll 20, the assembly l5 presents graduated reliefs, i. e., inequalities of the surface are formed as shown in Figure 2. The higher projections [9 are opposite the lower groups of type and the lower projections 19 are opposite the higher groups of type, while the powder 25 opposite the spacers 29 is uncompressed. The sheet 24 is then removed and the uncompressed or screened out powder 25 brushed off or otherwise removed from sheet 23. If adhesive 22 has not been forced through the screen 23, said screen may also be removed, and the resultant overlay will appear as shown in Figure 3. The agglomerated clusters of adhesive 22 and powder- 25 solidify and become hard as they dry. The overlay thus produced compensates for irregularities in the heights of the type form l4 and presents a hard solid backing for all portions of the form, whether high or low. One or more sheets of paper, cloth or similar material 30 may then be placed over the Overlay, as shown in Figure 4 and the apparatus is ready for printing.

Thus it can be seen that by means of the process described, an overlay can be simply and inexpensively prepared onthe impression cylinder or roll 20. The overlay need not be removed from the roll 20, hence it is in perfect register with the type form 14.

vA second means for receiving and retaining an impression from atype form !4 that may be employed in my process comprises a relatively porous fabric or the like containing particular types of powders loosely bound to each side thereof. The powders are of such composition that when commingled, they interact to form a stable Shape-retainingresinous or plasticcomposition. The powder on one side of the fabric or porous member may be, for example, .trioxymethylene, The powder .on the other side may then consist of a mixture of oxalic acid plus a compound such as-resorcinol, phenol, alkylphenols 1 such as paratertiary butylphenol, melamine; urea, or thiourea.

A typical assembly 16 conforming to this second embodiment is shown in Figure 8 and includes a layer of fabric 31 to one sideof which a layer of powderedtrioxymethylene 32 is loosely bound. A mixture 33 ofthe powders of resorcinol and-oxalic acid are carried by the fabric 3| on the other side thereof The oxalicacid catalyzes the -reaction between the other two materials. In carrying out my method, the assembly lliis Superimposed "9 min?,-P@F1d .;3l lPW??? ii'ig-roll as, following -which the typ form 14' is termingle with each other. When thetype form 14 is withdrawn, the assembly l6 presents the appearance illustrated in Figure 9. Advantageously, the particular powders used in this example react and cure at room temperature within a few seconds forming a relatively hard resinous composition in combination with the fabric 3|. The result is a rugged unitary overlay in which the resinous composition is combined with portions of the fabric 3I'and fills the interstices thereof, providing a hard, tough'backing for the printing process which is to follow. The unreacted powders which are screened out may be brushed or shaken off the fabric 31, leaving opposite and in register withthe groups of type (e. g., groups 21 and 28) complementary projections [8, as shown in Figure 10. When using some of the other mixtures listed above, it may be necessary to use temperatures somewhat higher than normal room temperature, in order to bring about and complete the reaction between the constituents. Overlays have been prepared in this manner that are accurate to-0.00025 inch, which is sufiicient for even the finest type of printing.

If the use of oxalic acid is objectionablebecause of the particular type of fabric used or for some other reason, a mixture of powdered trioxymethylene and a powdered alkali may be used as one component, and powdered resorcinol, phenol, urea, etc., may be used as the other. Still another alternative group of powders that may be used in my process in the manner described comprises powdered hexamethylenetetramine as one component, and powdered resorcinol, phenol, melamine, etc., as the other. Thus it can be seen that in this embodiment of my invention a number of different types of resinor plastic forming materials may be used with -substantially equivalent results, namely, the production of sturdy, accurate, comparatively inexpensive overlays. The particular types of powdered componentsused will depend upon such factors as kind and characteristics of the fabric or paper used, required reaction and curing temperature and time, degree of hardness of the resinous prod-. uct, etc. The proportions of the various reactants to be used and the-nature of the product obtained may be varied within limits, but in general I have found that the proportions normally used in the commercial manufacture of the par-' ticular type of resin or plastic employed give satisfactory results in my process.

I have also found that overlays'may be made in accordance with my invention from a single powdered substance of suitable composition, in combination with an appropriate fabric. For example, this third embodiment of my invention, shown in Figure 5, may comprise a wool fabric 36 coated with a powdered composition 31 containing polyvinyl chloride as the principal ingredient, such as the compositions sold under the trade name Geon. The type form I4 or plate is brought tobear upon the assembly 13 thus formed, compressing the composition 31 and forming a'compact mass with the fabric 36 at the desired points (Figure 6). The compressed powder composition 31 adheres tenaciously to the fabric 36 and frequently is sufficiently hard and-durable that further treatment unnecessary. The "uricbm pressed composition 31 is removed by shaking orbrushing following which the overlay assumes the appearance of Figure '7, viz., a surface of graduated reliefs I! which correct for the irregularities in the heights of the various groups of types of the type form [4. With certain of the polyvinyl chloride compositions, particularly those containing a vulcanizing agent, it is necessary to subject the fabric 36 containing the compressed composition 31 to temperatures slightly above room temperature-for example 15-25" F. above room temperature-in order to obtain the desired surface and strength characteristics. Again, 'a mild treatment with a suitable reagent maybe resorted to, to aid in curing the compressed powders.

Although the processes herein described, par-' overlay compensates generally for high and lowgroups of type rather than for individual type.

5 The overlays that can be prepared on the tympan roll without removal therefrom are especially suitable for use in machines because of their perfect register with the type form. r

From the foregoing, it will be apparent that I have invented an improved type of overlay that can be used with great advantage in the printing industry. The overlays herein disclosed are prepared by novel processes that are characterized by their simplicity and speed. A single impression of the type form or plate suffices to create an accurate contour on the overlay. In some cases, no other treatment is necessary; whereas in others only brushing, shaking, heating or cooling of the overlay, or the simple application of a suitable reagent thereto serves to complete the preparation of the same. My process completely eliminates the trial and error methods heretofore used in preparing overlays and dispenses with the need for highly skilled pressmen, since the processes herein disclosed may be practiced by printing operator-s possessing only ordinary skill.

While I have described certain preferred embodiments of my invention, it is to be understood that my invention is not limited thereto, inasmuch as various changes and modifications may be made without departing from the spirit of the invention, the scope of which is defined in the-appended claims.

I claim as my invention:

1. The process of forming an overlay which adhered clusters with the adhesive opposite the type, and thereafter removing the coated sheet.

2. The process of forming an overlay which comprises providing an impression member of a printing apparatus having positioned on the impression surface thereof an assembly comprising a base sheet material with an adhesivesurface. on one side thereof, a porous sheet matcrialln contact with said. adhe ive surface, and sheet loosely coated on one side with finely divided meta pa i les, the coated s de e n in contact. wit sa porous h e ate i pp yinsa typ form c a n t pe o different ei hts o aid assembly to thereby cause at least someo f the; partic es to a s t u the or us she -materrial and form adhered clusters with the adhesive opposite the type, and thereafter removing the coated sheet. Y

I 3. The process of claim 2 further characterized in that said finely divided metal particles cqm-. prise iron particles. v 7

4. The process of forming an overlay which; comprises providing an impression member of a printing apparatus having positioned on the pression surface thereof a porous sheet material having loosely adhered to one side thereof a finely divided solid material and having loosely adhered to the other side thereof another finely divided solid material capable of reacting with the first-named material to form a resin, applying a type form containing type of different heights to said porous sheet material to thereby cause at least a portion of one of the solid materials to penetrate into the porous sheet material and contact at least a portion of the other solid material, reacting said contacted portions to form a resin in adhered relation to the porous sheet material, and removing the unreacted finely divided materials.

The process of forming an overlay which comprises providing an impression member of a printing apparatus having positioned on the im-v pression surface thereof a porous sheet material having loosely adhered to one side thereof a f nely divided solid material comprising a component of a resin and having loosely adhered tothe other side thereof another finely divided SQlidmaterial comprising another component of a resin capable of reacting with the first-named component to form a resin, applying a type form containing type of different heights to said porous sheet material to thereby cause at least a portion ofone of the solid materials to penetrate into the porous sheet material and contact at least a portion of the other solid material, reactsaid contacted portions, to forma resin in adhered relation to the porous sheet material, and removing the unreacted finely divided ma ser als;

, 6. The process of forming an overlaywhich comprises providing an impression member of a printing apparatus having positioned on the impression surface thereof a porous sheet material having loosely adhered to one side thereof finely divided trioxymethylene and having loosely adhered to the other side thereof a finely divided 7 solid material capable of reacting with the tri- Qxyrnethylene to form a resin, applying a type form containing type of different heights to said porous sheet material to thereby cause at least a portion of the trioxymethylene to contact at least a portion of said finely divided solid material, reacting said contacted portions to form a resin in adhered relation to the porous sheet material, and removing the unreacted 'trioxymethylene and finely divided solid material.

' 7. The process of claim 6 further characterized in that. said finely divided solid material comprises a phenolic compound capable of reacting with trioxymethylene to form a resin.

7 8, Theprocessof claim 6 further characterized that said finely. divided solid material compr sest sorcmqlr 0- e-process oi f min an verla which mp i s; pro d n im r s o m mb r Qt a pr nt n apparatus harms p s io th 1 pression surface thereof a porous sheet material a n q c r dh o e s d the e f fine divided hexamethylene tetramine and havingloosely. adhered to the other side thereofa finely divided solid material capable of reacting with, thehexamethylene tetramine to form aresin, applying a type form containing type of differentv heights to said porous sheet material to thereby cause at least a portion ofthe hexamethylene tetramine to contact, atleast a portion of' said finely. divided solid material, reacting said Q0111 tacted portions to form a resin in adhered relate tion to the porous sheet'material, and remov ing the unreacted hexamethylene tetramine and finely divided solid material.

11. The process of claim 10 further character-v ized in that said finely divided solid material comprises a phenolic compound capable of reacte ing 'With hexamethylene tetramine to form a resin.

12. The process of claimv 10 further character: ized in that said finely divided solid material comprises resorcinol.

13. The process of claim 10 further characterizedin that said finely divided solid material is a member of the group consisting of ureaand thioureah i 14. Theprocess of forming an overlay which comprisesproviding an impression member of a printinglapparatus having positioned on the impression surface thereof a porous sheet material having loosely adheredthereto a finely divided solid compressible material capable of being transformed to a hard resinous structure, apply; ing a type form containing type of difierent heights to said porous, sheetmaterial to create an impression there'on'by compressing at least a portion of said powder, and fixing the impre's, sion by transforming the powder to a hard resin: ous structure.

15. The process of forming an overlay which comprises providing an impression member of a' printing apparatus having positioned on the impressionsurface thereof an assembly comprise ing a porous sheet material having loosely adhered theretoia finely dividedcompressible ma; terial capable of being or becoming hardened, applying to said assembly a type form containing types of different height and spacers, to compact said materialopposite said types into a reverse image of said type form, and thereafter remove ing the uncompacted material opposite said spacers,

16. The process of forming an overlay which comprises placing on the impression surface of a printing apparatus a sheet having loosely adhered thereto a, finely divided compressible ma terial capable of being or becoming hardened, applying to said compressible material the type form for which the overlay is to be made, said type form inluding high and low sections and spacers, whereby material opposite said high and low sections is compacted correspondingly and material O posite said spacers remains uncom-vi pacted, and thereafter removing the uncompacted material from-said sheet. v V

17. The process, of formingan overlay which comprises plac ng n a in ing a a u a.

9 porous sheet loosely coated on one side thereof with a finely divided compressible material and having means on the other side thereof for retaining material which passes through said porous sheet, applying to said compressible material the type form for which the overlay is to be made, said type form including high and low sections and spacers, whereby material opposite said high and low sections is compacted correspondingly and material opposite said spacers remains uncompacted, and thereafter removing the uncompacted material from said sheet.

18. The process of claim 14 further charac terized in that said finely divided solid compressible material comprises polyvinyl chloride.

ALFRED E. FARLEY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 715,561 Dethleffs Dec. 9, 1902 892,166 Lankes June 20, 1908 1,083,264 Baekeland Dec. 30, 1913 1,060,893 Dittman May 6, 1913 1,146,928 Cook July 20, 1915 1,233,799 Marzio July 17, 1917 1,441,283 St. Paul Jones Jan. 9, 1923 1,745,764 Lankes et al Feb. 4, 1930 2,199,597 Renfrew et a1 May '7, 1940 2,489,466 Schramm Nov. 29, 1949 

